High-performance and high-nitrogen austenitic stainless steel for non-magnetic drill collar and manufacturing method thereof

Abstract

The invention provides high-performance and high-nitrogen austenitic stainless steel for a non-magnetic drill collar and a manufacturing method thereof, and belongs to the technical field of stainless steel. The stainless steel comprises components in percentage by weight as follows: larger than or equal to 21.5% and smaller than or equal to 22.5% of Cr, larger than or equal to 0.5% and smaller than or equal to 1.5% of Mo, smaller than or equal to 0.040% of C, larger than or equal to 0.65% and smaller than or equal to 0.75% of N, larger than or equal to 0.40% and smaller than or equal to 0.50% of Nb, larger than or equal to 1.95% and smaller than or equal to 2.05% of Ni, larger than or equal to 16.0% and smaller than or equal to 17.0% of Mn, smaller than or equal to 0.20% of Si, smaller than or equal to 0.020% of P, smaller than or equal to 0.010% of S and the balance of Fe, wherein the sum of weight percentage of Cr, a product obtained by multiplying the weight percentage of Mo by 3.3 and a product obtained by multiplying the weight percentage of N by 16.0 is larger than or equal to 33.0%. The manufacturing method of the high-performance and high-nitrogen austenitic stainless steel comprises the steps as follows: smelting by an electric furnace, argon oxygen decarburization for secondary refining, electroslag remelting, cogging by a fast forging machine, forming by a radial forging machine and water cooling treatment. The high-performance and high-nitrogen austenitic stainless steel for the non-magnetic drill collar has the advantages of good room-temperature strength as well as excellent spot corrosion resistance and intercrystalline corrosion resistance.

Description

technical field [0001] The invention belongs to the technical field of stainless steel, in particular to a high-nitrogen austenitic stainless steel for high-performance non-magnetic drill collars and a manufacturing method thereof. Background technique [0002] Non-magnetic drill collars are an important part of today's high-precision, high-depth oil and gas drilling equipment, and one of the main components of the drill string, which can provide drilling pressure to the drill bit and improve the rigidity of the drill string. At present, the common non-magnetic drill collars are made of stainless steel with very low magnetic permeability, and the cross-section of the pipe body is circular inside and outside. Due to the needs of exploration and development, the drilling speed of drilling equipment is constantly accelerating, and the depth of drilling is also increasing. It is necessary to install measurement-while-drilling instruments and equipment to correct the vertical dir...

AI Technical Summary

Problems solved by technology

On the contrary, the addition of Mo element will lead to the formation of some brittle precipitates such as sigma phase or chi phase, which seriously deteriorates the plasticity and toughness of stainless steel

Images